What principle is used to transmit network data of smart phones, wireless signals such as am or FM, and why! Thank you! !

FM, mobile phones are all transmitted by FM, because FM transmission is characterized by narrow bandwidth and long distance, which is commonly used in mobile phones. Simply put, the ability to penetrate obstacles is weak, but the transmission distance is very long, which is why sometimes your mobile phone signal will be weak in the house, but because the mobile phone is far from the base station, it is suitable for FM transmission technology.

As for AM transmission, its characteristics are large bandwidth, short distance, strong penetration to obstacles, but short transmission distance, so AM transmission is generally used in smart home appliances, security engineering, alarms and so on.

Personal hand, hope to adopt, thank you.